What is the main function of the Button element in the user interface?

The Button element in the user interface serves to provide the user with an interactive element that can be clicked to perform a specific action. It is a primary control element that initiates events such as submitting a form, launching a function, or navigating to another screen.

Example in Node.js using Express and the EJS templating engine:

// In an EJS template
<button onclick="alert('Button clicked!')">Click me</button>

Although Node.js is a server-side platform, buttons are used on the client side for user interaction.